ProjectSummary Forsomethingascomplexandmultifacetedasbacterialantibioticresistance(AR),ourdrugevaluation paradigmisstrikinglynarrowandhomogenous:MIC/MBCtestinginstandardizedbacteriologicmedia.We haveshownthatthisdrugevaluationparadigmisinadequate,evenmisleading,aschangesinthemedia conditionsoftheprocedureleadtodramaticallydifferentresults.Amoreholisticdefinitionofantibiotictherapy thatcentersonunderstandingantibioticactivityinsynergywithhostinnateimmunefactorssuchascationic antimicrobialpeptides(AMPs),serumandphagocyticcells(e.g.neutrophils)revealstherapeuticoptions unrecognizedinstandardtesting.TheproposedU01programrepresentsagroundbreakingapproachtouse systemsbiologyapproachesandinformmoreeffectiveantibioticutilizationinthecontextofhostinnate immunity.Weproposeto:1)buildaniterativesystemsbiologyworkflowthatintegratesmultipleexperimental andcomputationalapproachestogiveacomprehensiveassessmentofAR?and2)applythisworkflowtohigh prioritypathogenstosystematicallyelucidateARmechanismsandtheirconditiondependency.Theiterative workflowincludes:(i)omicsandphysiologicaldatageneration.Clinicallyisolatedstrainsoftheselected pathogenswillbegrownunderconventionaltesting(bacteriologicmedia)andmorephysiologicconditions (tissueculturemedia,serum,andinpresenceofAMPsandneutrophils)toprobeforadvantageousgainof activity.Theomicsdatatypescollectedare:DNAresequencing,RNAseq,andmetabolomics.(ii) Bioinformaticsanddatamodelinganalysisinvolvesthreeapproaches:bigdataanalysisfordataset dimensionalityandcoarsegrainedvariabledependenciesassessment,genomescalemodelingfor mechanisticelucidationandanalysis,andmachinelearningthatusesARrelatedmetadatatoclassifythe overallbiologicalfunctions.ThisanalysiswillleadtounderstandingofARmechanisms.(iii)Multiscale validationfromanimalmodels,tolaboratoryevolution,tocytology,togeneexpressionalteration,tostructural proteinanalysisofputativetargets.Thevalidationthusrangesfromhostbehaviortoatomisticdetailof ligandtargetinteractions.Theiterativeloopthencloses,comparingcomputationalpredictiontoexperimental outcomes.Falsenegativeandfalsepositivepredictionsarethenalgorithmicallyanalyzedbyahypothesis generatingfamilyofalgorithmsthatthenmakessuggestionsaboutwhatconditionstouseinthenextiteration oftheloop.Thepathogensthatwewillfocusonaremethicillinresistant?Staphylococcusaureus?(MRSA),the carbapenemresistantEnterobacteriaceae(CRE)Klebsiella?pneumoniae?and?Acinetobacterbaumannii,?and Pseudomonasaeruginosa?.Theteamofinvestigatorshasmadethefoundationalobservationsandledthe developmentofthetechnologiesonwhichtheiterativeworkflowisbased.Amultiandgenomescalemethods ofsystemsbiologyfulfillsrequirementsofRFAAI14064towhichitresponds.